Revert "(Pre)Parser: Simplify NewExpression handling."

src/preparser.cc

Index: src/preparser.cc
diff --git a/src/preparser.cc b/src/preparser.cc
index 018f99d2b47b24dbfa7be11e9ba7dc6911db1644..6759550eb88c5bf9a19943bc828712166dfee88c 100644
--- a/src/preparser.cc
+++ b/src/preparser.cc
@@ -1007,7 +1007,12 @@ PreParser::Expression PreParser::ParseLeftHandSideExpression(bool* ok) {
   // LeftHandSideExpression ::
   //   (NewExpression | MemberExpression) ...
 
-  Expression result = ParseMemberWithNewPrefixesExpression(CHECK_OK);
+  Expression result = Expression::Default();
+  if (peek() == Token::NEW) {
+    result = ParseNewExpression(CHECK_OK);
+  } else {
+    result = ParseMemberExpression(CHECK_OK);
+  }
 
   while (true) {
     switch (peek()) {
@@ -1047,28 +1052,35 @@ PreParser::Expression PreParser::ParseLeftHandSideExpression(bool* ok) {
 }
 
 
-PreParser::Expression PreParser::ParseMemberWithNewPrefixesExpression(
-    bool* ok) {
+PreParser::Expression PreParser::ParseNewExpression(bool* ok) {
   // NewExpression ::
   //   ('new')+ MemberExpression
 
-  // See Parser::ParseNewExpression.
-
-  if (peek() == Token::NEW) {
+  // The grammar for new expressions is pretty warped. The keyword
+  // 'new' can either be a part of the new expression (where it isn't
+  // followed by an argument list) or a part of the member expression,
+  // where it must be followed by an argument list. To accommodate
+  // this, we parse the 'new' keywords greedily and keep track of how
+  // many we have parsed. This information is then passed on to the
+  // member expression parser, which is only allowed to match argument
+  // lists as long as it has 'new' prefixes left
+  unsigned new_count = 0;
+  do {
     Consume(Token::NEW);
-    ParseMemberWithNewPrefixesExpression(CHECK_OK);
-    if (peek() == Token::LPAREN) {
-      // NewExpression with arguments.
-      ParseArguments(CHECK_OK);
-    }
-    return Expression::Default();
-  }
-  // No 'new' keyword.
-  return ParseMemberExpression(ok);
+    new_count++;
+  } while (peek() == Token::NEW);
+
+  return ParseMemberWithNewPrefixesExpression(new_count, ok);
 }
 
 
 PreParser::Expression PreParser::ParseMemberExpression(bool* ok) {
+  return ParseMemberWithNewPrefixesExpression(0, ok);
+}
+
+
+PreParser::Expression PreParser::ParseMemberWithNewPrefixesExpression(
+    unsigned new_count, bool* ok) {
   // MemberExpression ::
   //   (PrimaryExpression | FunctionLiteral)
   //     ('[' Expression ']' | '.' Identifier | Arguments)*
@@ -1119,6 +1131,14 @@ PreParser::Expression PreParser::ParseMemberExpression(bool* ok) {
         }
         break;
       }
+      case Token::LPAREN: {
+        if (new_count == 0) return result;
+        // Consume one of the new prefixes (already parsed).
+        ParseArguments(CHECK_OK);
+        new_count--;
+        result = Expression::Default();
+        break;
+      }
       default:
         return result;
     }